1. Field of the Invention
This invention relates to a sluicing valve device, and more particularly to a sluicing valve device having case members attachable to a pipe, and a valve element which is arranged in the case members and can be inserted into a hole formed in the pipe.
2. Description of the Related Art
In the case where piping work of water supply or the like is carried out, there has been employed a method in which water flow in the pipe is temporarily stopped using a sluicing valve device which is a water supply suspension device for non-water-cutting off pipe line while maintaining a non-water-cutting off state without cutting off the water flow on the upstream side, the work is carried forward on the downstream side, and after completing the work, the state of stopping the water is released.
Conventionally, in a valve element used as the water supply suspension device for non-water-cutting off pipe line, a rubber lining tends to be large in volume. This is because the water supply suspension device for pipe line is designed to stop water by inserting the valve element into a pipe line laid underground in which water is flowing, so that positioning of a bore hole opening and the valve element on site is required. Accordingly, in order to securely shut down the water flow, the rubber lining cannot help being large in volume. In other words, stopping the water in the pipe depends on elasticity of the rubber lining.
Furthermore, with regard to the pipe in which the water supply suspension device for non-water-cutting off pipe line is set up, there is one used for long years after laying underground, relatively new one, etc. and thus even pipes with the same outside diameters commonly have different inside diameters from each other. As a result, in order to improve a water stopping performance, the rubber lining cannot help being large in volume.
On site, in order to securely stop the water in the pipe, it is necessary to satisfy the following conditions and to adjust balance.
(1) Compressive force of the rubber lining between a bottom portion of the valve element and a bottom portion of the pipe inner surface is made to act.
(2) Compressive force of the rubber lining between a side surface of the valve element and a side surface portion of the pipe inner surface is made to act.
(3) The bore hole opening is blocked by an upper portion of the valve element.
With regard to (1) and (2), although an increase of the rubber lining in volume allows conditions to some extent to be addressed, a deformation amount of the valve element becomes large when shutting the valve element, and torque required for shutting the valve element from contact of the valve element with the bottom of the pipe until water is completely stopped tends to be large. When the deformation amount is large, sufficient compressibility with the pipe inner surface can hardly be obtained, and thus a sufficient water stopping performance cannot be achieved. There, therefore, has been a problem that repetition of opening and closing operations causes the rubber lining to be damaged by the bore hole opening. With regard to (3), after securely blocking the inside of the pipe according to (1) and (2), the bore hole opening is required to be blocked. If the bore hole opening is precedently blocked, a flange portion of the rubber lining comes into contact with the bore hole opening and shutting torque is increased, thereby preventing the compression of the valve element rubber lining from being transmitted to the pipe inner surface. As a result, further fastening causes a problem that the rubber lining is damaged by the bore hole opening.
In this manner, it is necessary to adjust the balance of the above-mentioned (1) to (3) with respect to existing piping with various inside diameters, and thus there is a demand for a water supply suspension device for non-water-cutting off pipe line having a higher water stopping performance.
Accordingly, the applicant of the present invention has developed a sluicing valve device described in Japanese Patent Application Laid-Open No. 2003-343748. This sluicing valve device has a spindle and a valve rod which are inserted into a pipe as a driving shaft, and a movable piece bringing a seal member into pressure contact with a wall surface inside of a pipe, which enables water to sufficiently stop. In addition, the vertical size can be smaller than that of conventional one.
However, there is a problem that this sluicing valve device has a number of components and a complex structure, thereby leading to a high manufacturing cost.